Control Cables Explained: Types, Structure, Standards and How to Choose the Right One

This article walks through what control cables are, how they are constructed, the common types and voltage grades, and practical tips for selecting the right cable for a project. It is written as a general knowledge reference for engineers, procurement teams and anyone learning about industrial cabling.

1. What Is a Control Cable?

A control cable is an electrical cable designed to transmit control signals rather than deliver large amounts of power. It carries low-voltage signals between control devices such as programmable logic controllers (PLCs), sensors, actuators, relays, motor starters and instrumentation panels.

Typical applications include:

• Industrial automation and process control lines
• Instrumentation and monitoring systems
• Elevator and conveyor control circuits
• Switchgear and motor control centers
• Mining, energy and traffic control systems

Because these cables often run in multi-core bundles carrying dozens of individual signal circuits, they need to combine flexibility, reliable insulation and, in many cases, shielding against electromagnetic interference.

2. Basic Structure of a Control Cable

While designs vary by standard and application, most control cables share a similar layered structure:

3. Common Control Cable Types (KVV Series)

Many control cables used across power, mining and automation industries follow a naming convention where letters describe the conductor, insulation, screening and armour type. The table below summarizes the most common variants.

4. Typical Technical Parameters

Control cables are generally rated for lower voltages than power cables, since their job is signal transmission rather than delivering heavy current. Common parameters include:

5. How to Choose the Right Control Cable

Selecting a control cable is not just about cost — the wrong choice can lead to signal interference, insulation failure or premature wear. A few key questions help narrow the decision:

• Is the cable fixed or moving? Flexible types like KVVR suit moving parts; fixed types like KVV are cheaper for static installations.
• Is interference a concern? If the cable runs near motors, VFDs or high-power lines, a shielded type (KVVP, KVVP2) helps prevent signal noise.
• Will it be buried or exposed to mechanical stress? Armoured types (KVV22) offer added protection against crushing or impact.
• Is fire safety a requirement? Flame-retardant (ZR) versions are often mandated in enclosed or public buildings.
• What is the operating environment? Temperature range, moisture exposure and chemical resistance all affect insulation choice.

6. Frequently Asked Questions

Q: What is the difference between a control cable and a power cable?
A: Power cables are designed to carry large electrical loads to run equipment, while control cables carry low-voltage signals used to monitor and control that equipment.

Q: Can control cables be used outdoors or underground?
A: Yes, armoured types such as KVV22 are designed for direct burial or outdoor trenching where mechanical protection is needed.

Q: Why do some control cables have a shield?
A: Shielding reduces electromagnetic interference from nearby power equipment, which helps keep control signals accurate and stable.

Q: How many cores can a control cable have?
A: Control cables are commonly available from 2 cores up to more than 60 cores, depending on how many circuits need to be managed.

Q: What does the "450/750V" rating mean?
A: It indicates the cable's rated voltage range — 450V phase-to-earth and 750V phase-to-phase — under normal operating conditions.

Final Thoughts

Control cables may not carry heavy power loads, but they form the nervous system of industrial and automated systems. Understanding the differences between fixed, flexible, shielded and armoured types makes it much easier to specify the correct cable for a given project, helping avoid signal issues, premature failure or safety risks down the line.